Calculator



Patented Jmu L 192% n. A. WRENN,

CALCULATOR.

APPLICATION man APH. 4. 1917. RENEWEU ma,

ATTORNEYS m QT wir

fiiigi fyi H. A. WRENN.

CALCULATOR.

APPLICATION FILED APR. 4. 1917. RENEWED DEC. 24, I9I'9. Y

' 1,341,962. Patented June 1, 19201,

3 SHEETS-SHEET 2.

H. A. WRENN.

CALCULATOR.

APPLICATION man APR.4,1917. AENEWED DEC. 24. |919.

1934192- Patented June l, 1920.J

3 SHEETS-SHEET 3.

, 5% urli/Hm@ l @A TTOBWE YS UNITED STATES PATENT oF-FICE.

HERBERT A. WRNN, OF WASHINGTON, DISTRICT OFl COLUMBIA, ASSIG-NOR- TO THEtURENN ADDING MACHINE COMPANY, OF WASHINGTON, DISTRICT OF COLUMBIA,

A CORIORATION OF DISTRICT OF COLUMBIA.

CALCULATOR.

. Application led April 4, 1917, Serial No. 159,696.

To all lwhom t 'may concern.'

Be `it known that I, HERBERT A. VRENN, a citizen of the United States,and a resident of lVashington, in the District of Columbia, haveinvented a new and useful Improvement in Calculators, of which thefollowing is a specification. Y My present invention relates generallyto calculators and consists` more particularly in certain improvements over and in connection with my Patent, No. 1,181,819, dated May 2, 1916.

The primary object of my present 11nprovement is to provide means inconnection with the well known chain type of calculators, whereby toeffectively prevent overrunning either in the manipulation of the chainsin use or the resetting of the series of number vwheels, and a furtherobject relates more particularly to improvements in the zero settingmechanism.

Still further .objects relating for the most part to details ofconstruction to be hereinafter more fully described, will be betterunderstood from the following' description of the construction,arrangement and operation of the several part-s, reference being had tothe accompanying drawings, formi ing a part of this application,whereinf Figure 1 is a: front elevation of my improved calculator,partly broken away and in section,

Fig. 2 is a vertical transverse section taken substantially on line z-Qot Fig. v1`

Fig. 3 is a detail perspective view orl one -V of the transfer levers.

Fig. -l is a detail perspective view ot ,one of the chain lockingplat-cs,

Fig. 5 is a detail horzontal section taken substantially on line of Fig.1.

Fig'. G is an enlarged sectional view corresponding to the lower portionof 2.

Figs.` 7 and 9 are vertical sections taken on line 8 8 of Fig. '1.illustrating two positions of one of the number wheels.y in conneet-ionwith portions of the transfer mechanism,

Fig'. 9 isa sectional view along a similar linelooking in the oppositedirection.

Fig. 10`is a detail perspective view ot a portion of one of the chains,y

Figs; 11 and 12 are respectively' a side Specification of LettersPatent.

Patented June 1, 1920.

Renewed December 24, 1919.` Serial No. 347,195.

forming between them channels in which the Chains 1S travel, and thekeyboard as seen particularly at 19 in Fig. 5 having recesses in the`bases of the channels between the guides 1T into which the numberedstrips 20 are disposed either with or without protecting coverings 21 ofglass. mica or other suitable transparent or translucent material.

The casing 16 has a front opening exposing the .major portion ot thesurface of the y keyboard and has upper and lower front wall sections Q2and 23, as seen in Figs. 1 and 2, the upper section 22 of which isprovided with a. series of horizontally alined and spaced openings 24 inalinement with the channels between the several guides 17 of thekeyboard` and the lower section 23` of which is provided with an upperedge-25 adjacent tliellower portion or the keyboard, which l'orins apermanent rigid stop for the. operatous fingers working downwardly inthe channels ot' the keyboard in the operation ot the machine aspresently described.

Mounted through the upper portions of the side walls oit the Ytraine l5is a shat't 26 on which are a series of number wheels 27 equal in numberto the openings i4 of.' 'the casing and the channels ot the keyboard,each of said wheels having a tooth-like numbered peripheral surface, thegrooves 28 between the numbered facets oli which receive thecross bars29 of the links of the respective chain 18,the chain passing upwardlyaround the number wheel as seen particularly in Fig. 2 and as well knownin this un of each chain entends 'uide cha nucl of the keyin Fig. 2, thelower end of the chain passing 'around a cross bar 30 secured throughthe upper fr'ee ends of the extensions 31 of a U-shaped tension member,the lower cross bar 32 of which is engaged by the'forward hook end of aspring 33, the latter anchored to a stationary cross bar 34 of the frame15.

Each of the extensions 31 of each tension member has a V-shaped notch inits rear edge adjacent the cross bar 32 for the reception of the forwarddownwardly inclined knife edge 85 of a bearing cross bar 3G, whichpermits the tension member to yield on the bearing thus formed withoutundue friction as each link of its respective chain 18 passestherearound, as plainly seen by a comparisonof Figs. 2 and 6, suchmovement of course being under tension of the spring 33.

It is understood, of course,that the tension members extend in a seriesalined with the several operating' chains 18 and that the numberedfacets of the number wheels 2.7 are arranged to show through theopenings 24 of the casing so that by placing his linger upon that crossbar of the chain 18 in one of the channels immediately below the desirednumber in the base of the channel, the operator by then moving hisfinger downwardly until further motion is arrested by the stop 25, mayturn the respective number' wheel to show the desired numberthrough therespective sight opening 24.

In starting operation with the several number wheels in the Zeroposition shown in Fig. 1, the first channel at the right hand side isutilized unless a number consisting of more than one figure is to beregistered.

The transfer mechanism includes a cross rod 37 at the rear of and/parallel with the shaft 2G on which are pivoted at their rear ends aplurality of transfer arms 38, these arms being positioned between theseveral number wheels 27 and provided at one side with intermediatelaterally projecting rollers 39, the forward extremities of these 'armsbeing pivotally connected to the upper extremities of forwardly anddownwardly inclined transfer levers 40, de pending in a series in spacedrelation beneath the keyboard 19, with their lower offset ends 41working through a transverse guide bar 42 and provided with upwardlyinclined lower angular extremities 43, the lower extremity of each leverbeing thus positioned in vertical alinement with the lower portion ofthe chain 18 of the next adjacent number wheel to the left thereof.

Each of the number wheels 2T has at its left side a laterally projectingcam 44, which in the rotation of the number wheel in operation worksagainst the rollerI 39 vof its respective transfer arm 38 to graduallylift the same a distance equal to the length which permits the roller 39and the respec` tive arm 38 to drop when the end of the cam is reachedand provide for lowering movement of the respective transfer lever 40,the lower angular extension 43 of which operates against that cross barof its respective operating chain 18, previous to which it has beenelevated above, to thus force the chain downwardly and rotate thecorresponding number wheel a single space. To this end each transferlever 40 is engaged at an intermediate point by the upper end of aspring 46 the lower end of which is anchored to the guide bar 42 beforementioned.

Referring to Figs. 7 and 8 it will be noted that each number wheel 27 isprovided with a laterally projecting pin 47 `spaced from the upperportion of the cam shoulder 45 a distance just suiiicient to admit ofthe passage of the respective roller 39 between f moves over the end ofthe cam so as to thus promptly and effectively check further movement ofthe respective number wheel and obviate the danger of overrunning in theoperation of the Zero mechanism t0 be presently described.

lirconstructing the apparatus the first number wheel at the right ispreferably set slightly in advance of the others in respect to itsdirection of rotation in order to provide for the release of the partsoperating the next adjacent number wheel of the series, slightly inadvance of all others, in the zero setting operation in the linterest ofwhich an operating handle 48 is provided as best seen in Fig. 1, havinga socket portion 49 extending through an opening in one side of thecasing 16 and engaging the adjacent end of the shaft 26 whereby rotationof the handle will impart similar rotation to the shaft.

Each of the number wheels 27 has a hub portion 50 loosely disposed onthe shaft 2G as best seen in Fig. 9 and is further provided with aradial spring arm 51 anchored thereto at theouter end of the arm, theinner end of which projects through a` slot 52 of the hub 50 forengagement with the periphery of the shaft 26. Adjacent each of thewheels the shaft i: cut away to form a shoulder over which the end ofthe spring 51 freely passes in the normal rotation of the number wheelin the direction indicated by the arrow in Fig. 9, at the same timeproviding for engagementof the shoulder with the inner end of the springarm i the number wheels will be reset to the Zero position as shown inFig. l.

In order to 'prevent movement of the handle 48 beyond the full strokewhereby to prevent overrunnng of the shaft 26, a spring stop preferablyof the form shown in Figs. ll and l2 is utilized attached to theadjacent side wall of the casing 16,this spring stop including anupwardly projecting spring arm 54 having a cam shaped head 55 which, inthe movement of the lever 48 toward the stop in the direction of thearrow of Fig. l1 is engaged by a laterally projecting pin 56 of the saidlever to move the spring arm 54 to the position shown in dotted lines inFig. 1l. The arm has a horizontal angular stop piece 57 below its head55 into engagement with which the pin 56 moves when the arm 5l is in thedotted line Aposition of Fig. l1, so as to prevent `further downwardmovement of the I lever, the pin 5G being then in the position shown indotted lines at 56L in Fig. 1l, and the arm 54: being prevented fromreturn movement from its position shown in dotted lines in Fig. ll byvirtue of a shoulder 58 above which the Vlever pin 5G must besubsequentlyelevated. When the pin is elevated the spring arm 54 willreturn to the 'operating chain, in movement normal position in fulllines in Fig. l1 and the lever will then be free for subsequent movementin the next Zero setting operation in the proper direction, its movementin the reverse direction lbeing prevented by a lug 59 of the spring arm54.

It is obvious that in the operation ot a calculator of the present typea hurried or jerky motion of the operators fingers, even though limitedto some extent by the stop 25 ot the casing, is calculated tobring aboutoverrunning of the operating` chains at times, and thus over-'running ofthe number wheels, a disadvantage which l seek to overcome by theprovision of means capable et movement adjacent the stop 25 in normalope 'ation and which, upon engagement by the operators lingers. willetiectively lock the chains against further movement and thus againstoverrunning.

l therefore provide an upwardly and rea rwardly inclined locking plate(it) as shown in Fig. l having its uppe angular end Gl extending intothe lower open end or the respective Ouide channel of the keyboard lil,and provided at its lower end with depending side arms G2, the lowerextremities ot' which are pivotally mounted upon the projectingextremities of the cross rod 30 ot the respective tension member 8lbefore described, so that as each link oit the respective around thecross rod 30, rocks the respeIl ive member 31, -the respe will beelevated to t end 61, normally hush shown in Fig. 2, to a pont'above thesaid stop as shown in Fig. 6. Thus as each cross bar of each of thechains reaches the stop 25, the respective stop plate 6() will be incourse of elevation, and upon being engaged by the operators finger,will lock the tension member, and in this manner act as an effectivecheck against further and overrunning movement ot' the respectiveoperating chain. lt is thus obvious from the foregoing that my inventionprovidesa calculator of the present type capable of a generally moreeffective and more eiiicient operation in uses to which such anapparatus is generally assigned, and that vmy improvements in eachinstance materially contribute to greater usefulness and capabilitieswithout adding materially to the constructive cost thereof and withoutunduly con'iplicating the same.

l claim l. A lalculating apparatus of the character described includinga keyboard, a series of number wheels above the keyboard, link operatingchains, the upper runs of which extend over the keyboard and whichproject around the number wheels at their upper ends, tension members atthe lower ends of the chains, each of saidtension members including apivoted U-shaped piece, the `free lends of which are connected by a rodaround which the lower end of the respective chain pas; springs engagingthe cross-bars of said U-shaped tension members, and `locking plates.adjacent the lower end of the keyboard pivotally connected to the saidtension members and vertically shittable upon rocking movements ot thesaid tension members, for the purpose described.

2. A calculating apparatus of the characterV described including akeyboard, a series of number wheels above the keyboard, link operatingchains, 'the upper runs of which extend over the keyboard and whichproject around the number wheels at their upper ends, tension members atthe lo ver ends ot the chains, each of said tension members inclluling apivoted ntl-sliaped piece, the free ends ot which are connected by a rodaround which the lower end of the respective chain passes, springsengaging theI ross bars ot said U-shaped tension members, and lockingplates adjacent the lower end otthe keyboard pivotally connecte( membersand vcrticalljv s ing movements ot the s l tension mei said lockingplates having the upjazr ai finger engaging ends and provided dependingside extensions having apertures at their lower ends receiving theestremi- 'ties ot the cross rods ot the tension mefnbers.

8. calculating apparatus ot the chaisacter described comprisinfy r keseries of number wheels at the 'upper the keyboard` link oj'iafra'iingchains llO ends around the said number wheels, tension members engagingsaid chains at their lower ends and vertically shiftable locking membersoperating adjacent the lower end of the keyboard and connected to, andshiftable vertically by, the said tension members.

4. A calculating apparatus of the character described having a keyboardprovided withl channels, finger actuated chains movable in saidchannels, number wheels at the upper end of the keyboard around whichthe upper ends of the chains travel, tension members around portions ofwhich the lower ends of said chains extend, and locking members forcheckingr movement of the chains consisting of' plates adjacent thelower end of the keyboard having upper angular ends extending into thelower ends of the said channels of the keyboard and connected at theirlower ends to and shiftable by the said tension members.

5. A calculating apparatus of the character described having a keyboard,a series of' number wheels, link operating chains extending over thekeyboard and around said number wheels at one end, tension membersengaging said chains at their opposite. ends 'and means connected tosaid tension members and manually actuated to check movement oi saidchains.

(l. In an apparatus of the character described thc combination ofoperating chains, a keyboard on which the said cha-ins operate having afinger stop and manually actuated means adjacent the finger stop forchecking movement of the chains.A

7. In an apparatus olf the character described the combination o'lEoperating chains,

' a kevboard on which the said chains operate,

having a linger stop and manually actuated means adjacent the fingerstop for checking movement ot' the chains, said means consisting of'vertically shi'f'table locking members normally moved by the chains.

8. In an apparatus otI the character described, the combination of akeyboard having a lower finger stop, number wheels, operating chainsextending over the keyboard and around the number wheels, means totension the said chains, and means to prevent overrunning of the chainsin use consisti ,g of' members arranged adjacent the said linger stopand vertically reciprocated during normal movement of the said chains,whereby pressure upon the said members will check movement of` the saidchains.

9. In a calculator of the type described, a series of number wheels, aseries of operating chains extending at one end around said numberwheels and tension members at the opposite ends of said chains includingU-shaped pieces having their extensions provided with inteimediateV-shaped recesses` a cross bar connecting the extensions olE saidmembers and around which the adjacent end of therespective chain passes,and a cross bar forming a bearing for said tension members and having aknife edge extending into the V-shaped recesses of the4 said members.

l0. In an apparatus of the character described, the combination ofoperating chains, a keyboard on which said chains operate, and manuallycontrolled means adjacent the lower portion of the keyboard for checkingmovement of the chains.

l1. In an apparatus of the character described, the combination ofoperating chains, a keyboard on which said chains operate, and a fingerengaging member for each chain for checking movement thereof, arrangedin the path of movement of the chain.

l2. In anapparatus of the character described, a calculating mechanismincluding by checking of movement of the stop mem-- bers will check theoperating members and prevent their overrunning. f

13. In an apparatus off the character described, the combination oi anendless movable operating member and a manually controlled stop membernormally moved by the operating member and disposed adjacent to the pathof movement thereof.

14. In apparatus of' the character described. the combination with atotalij/,er` olf a movable endless belt operating member therefor,adapted to be shifted by the finger of' the operator or by a stylus heldin the hand of' the operator, and means to hold the endless beltoperating member against overrunning nuivenunt, said means being a1'-ra'nged near the endless belt operating member to be actuated by thefinger or stylus which is employed to move the endless belt operatingmember.

15. In appa "atus of the character described, the combination with atotalizer, of a movable operating member therefor, adapted to be shiftedlongitudinally by the finger of the operator or a stylus held in thehand of the operator, and means to prevent over-running movement of themovable operating member, including an element arranged near and uponone side of the movable operating member to be thereby dislposed in thepath of travel of the finger or indicia bearing member and adapted to beoperated by the finger or stylus simultaneously With the operatingmember whereby the indicia bearing member Will be checked stylus held inthe hand ofthe operator, and

means arranged in the path of travel of the nger or stylus for checkingthe rotation of said rotating element.

18. In a device of the type described a totalizer, an operating membertherefor'embodying a plurality of simultaneously shiftable elementsadapted to be engaged by the finger of the operator or a stylus held inthe hand of the operator, and means for locking said operating memberagainst movement in one direction when the operating member has beenshifted a predetermineddistance.

19. Ina device of the type described, a totalizer, an operating membertherefor, embodying a member adapted to be shifted by the nger of theoperator', or aYY stylus held in the'hand of the operator, and meansadjacent' said operating member and operated simultaneously therewithwhen the operating member has been shifted a predetermined distance,'for checking the motion of 3b said totalizer. y

HERBERT A. WRENN. Witnesses:

STERLING H. WA'rso, LINwooD A. WALTERS.

